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  <title>十进制转换为十六进制</title>
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  <div id="layout-content"><div id="function.dechex" class="refentry">
   <div class="refnamediv">
    <h1 class="refname">dechex</h1>
    <p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">dechex</span> &mdash; <span class="dc-title">十进制转换为十六进制</span></p>

   </div>
 <div class="refsect1 description" id="refsect1-function.dechex-description">
  <h3 class="title">说明</h3>
     <div class="methodsynopsis dc-description">
      <span class="methodname"><strong>dechex</strong></span>
       ( <span class="methodparam"><span class="type">int</span> <code class="parameter">$number</code></span>
      ) : <span class="type">string</span></div>

    <p class="para rdfs-comment">
     返回一字符串，包含有给定
     <code class="parameter">number</code>
     参数的十六进制表示。
    </p>
  <p class="para">
   所能转换的最大数值为十进制的
     <strong><code>PHP_INT_MAX</code></strong><em> * 2 + 1</em> (或
   <em>-1</em>)：在 32 位平台上是十进制的 <em>4294967295</em>，其 <span class="function"><strong>dechex()</strong></span> 的结果为 <em>ffffffff</em>。
  </p>
   </div>

 <div class="refsect1 parameters" id="refsect1-function.dechex-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<code class="parameter">number</code></dt>

     <dd>

      <p class="para">
       要转换的十进制值
      </p>
      <p class="para">
       PHP 的 <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span> 类型是有符号的，但 <span class="function"><strong>dechex()</strong></span> 处理无符号整数，负正数会以无符号处理。
      </p>
     </dd>

    
   </dl>

  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.dechex-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   <code class="parameter">number</code> 的16进制表示
  </p>
 </div>

 <div class="refsect1 examples" id="refsect1-function.dechex-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-4122">
    <p><strong>Example #1 <span class="function"><strong>dechex()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">echo&nbsp;</span><span style="color: #0000BB">dechex</span><span style="color: #007700">(</span><span style="color: #0000BB">10</span><span style="color: #007700">)&nbsp;.&nbsp;</span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />echo&nbsp;</span><span style="color: #0000BB">dechex</span><span style="color: #007700">(</span><span style="color: #0000BB">47</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
a
2f
</pre></div>
    </div>
   </div>
  </p>
   <p class="para">
   <div class="example" id="example-4123">
    <p><strong>Example #2 大整数的 <span class="function"><strong>dechex()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #FF8000">//&nbsp;The&nbsp;output&nbsp;below&nbsp;assumes&nbsp;a&nbsp;32-bit&nbsp;platform.<br />//&nbsp;Note&nbsp;that&nbsp;the&nbsp;output&nbsp;is&nbsp;the&nbsp;same&nbsp;for&nbsp;all&nbsp;values.<br /></span><span style="color: #007700">echo&nbsp;</span><span style="color: #0000BB">dechex</span><span style="color: #007700">(-</span><span style="color: #0000BB">1</span><span style="color: #007700">).</span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />echo&nbsp;</span><span style="color: #0000BB">dechex</span><span style="color: #007700">(</span><span style="color: #0000BB">PHP_INT_MAX&nbsp;</span><span style="color: #007700">*&nbsp;</span><span style="color: #0000BB">2&nbsp;</span><span style="color: #007700">+&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">).</span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />echo&nbsp;</span><span style="color: #0000BB">dechex</span><span style="color: #007700">(</span><span style="color: #0000BB">pow</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">32</span><span style="color: #007700">)&nbsp;-&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">).</span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
ffffffff
ffffffff
ffffffff
</pre></div>
    </div>
   </div>
  </p>
 </div>

 <div class="refsect1 seealso" id="refsect1-function.dechex-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="hexdec.html" class="function" rel="rdfs-seeAlso">hexdec()</a> - 十六进制转换为十进制</span></li>
    <li class="member"><span class="function"><a href="decbin.html" class="function" rel="rdfs-seeAlso">decbin()</a> - 十进制转换为二进制</span></li>
    <li class="member"><span class="function"><a href="decoct.html" class="function" rel="rdfs-seeAlso">decoct()</a> - 十进制转换为八进制</span></li>
    <li class="member"><span class="function"><a href="base_convert.html" class="function" rel="rdfs-seeAlso">base_convert()</a> - 在任意进制之间转换数字</span></li>
   </ul>
  </p>
 </div>

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